Christmas Island discovery redraws map of life
The world's animal distribution map will need to be redrawn and textbooks updated, after researchers discovered the existence of 'Australian' species on Christmas Island.
The University of Queensland's Professor Jonathan Aitchison said the finding revises the long-held understanding of the location of one of biology and geography's most significant barriers - the Wallace line.
"The Wallace line - named after its discoverer Alfred Russel Wallace - delineates major biological division separating the species with Asian origins from those with Australasian ones," Professor Aitchison said.
"It runs along the narrow seaways separating Bali from Lombok, and Borneo from Sulawesi.
"To the west are the tigers, elephants, rhinoceroses and orang-utans of Eurasia and to the east, the marsupials and monotremes that are synonymous with Australia."
Working 1000 kilometres west of the conventional trace of Wallace line, on Christmas Island, Professor Aitchison and his colleagues, Dr Jason Ali from the University of Hong Kong and Professor Shai Meiri from the University of Tel Aviv, noted species with Australasian origins.
"Unexpectedly, half of Christmas Island's land mammal and land reptile species - two rats, two skinks and one gecko - have a genetic heritage to Australia's side of the divide," Dr Ali said. ...
